Literal translation: Tissue(paper) heart. Thus, easily torn (refer: 'koyak'). 'Hati' is technically liver, but for most use-cases it translates to heart, e.g. 'sakit hati' means heartache.
A person/entity with 'hati tisu' is easily hurt (refer: 'koyak') at the slightest insult.
Kalau hati tisu, tak boleh kena kecam tak payah nak menulis di socmed.
Translation: Don't post/write on social media if you're easily hurt and can't take criticism.
Hati is the name of a mythical wolf in Grímnismál. He is the son of Hróðvitnir and the father of Hrímgarðr. Snorri records in Gylfaginning that he runs in front of the sun and pursues the moon Máni which it will eventually devour. The wolf Skǫll follows the sun. Another name for him is Mánagarmr.
While our lifespan is the number of years we will live, our healthspan is the number of healthy years we will have and our sexspan is is the number of years we will continue to be healthy enough to continue having an active sex life.
A lighthearted reaction upon receiving disappointing news of some sort. Usually something that isn't a particularly a big deal, esp. when it primarily affects someone else - sort of a mild schadenfreude. Sometimes doubled or tripled, and possibly said in a sing-songy voice for added comedic effect to imitate a muted trumpet, which is how the meme originated.